In recent weeks, Republican Sen. John McCain has asked both President Bush and Democratic nominee John Kerry to condemn certain ads produced by outside interest groups. Senator McCain considers the ads, which attack both candidates' military records, over the top when it comes to negativity.

Intuition should tell Americans, and the candidates, that he's right. But his background also gives him finger-wagging rights, as a Vietnam war hero who himself ran a hardscrabble race for the White House in 2000, and one whose signature Senate achievement has been campaign-finance reform.

McCain has had some success with his efforts so far, at least with Mr. Kerry. Last week he called on his fellow veteran and Senate friend to publicly condemn an ad produced by the liberal group, MoveOn.org, that criticizes Bush's service in the Texas Air National Guard. Kerry did, issuing a statement that the ad is inappropriate. "This should be a campaign about issues, not insults," said Kerry. Unfortunately, MoveOn.organnounced last Wednesday that it would keep airing the ads attacking Bush.

McCain has also called on the president to condemn an ad produced by "Swift Boat Veterans for Truth" that shows veterans saying Kerry lied about his Vietnam service. The White House refused, implying at least tacit support of the ad's claims. Now the Kerry camp is launching a counter ad, and plans to file a complaint against the Bush campaign with the Federal Election Commission.

McCain says both Bush and Kerry served honorably in the military, and rightly notes the acute lack of civility: "This is the bitterest, most unsavory campaign in the nation's history."

One can't overlook McCain's own political interest in the ads issue. Although he denies he'll run again for president, his fairness in this case burnishes his credibility with independent voters. And he's polishing the Republican base by addressing the upcoming GOP convention and campaigning enthusiastically for a man he's often criticized, President Bush.

But so what if McCain's role as civility cop involves a political side benefit for him? The tone of this campaign needs to be turned around, and if the firebrand can help do that (and at the same time keep up the pressure on Bush), more power to him.